Check out Room and Board. They have a tulip table called Aria. It is not listed on the website but you can just buy the base. You will need to call their toll-free number. I did this. But, if I remember correctly when I did some sleuthing for "tulip table base" or "trumpet table base" a Canadian manufacturer came up in my search but they would not ship to the U.S. Sorry I do not remember the name.

Just make sure the base can handle the weight of a heavy top.

Also, the R&B table tops in quartz or granite do not secure to the base. I really dislike this and several people in the reviews have asked about it. Personally, no matter what you do, make sure it is secure. A banquette requires a lot of squeezing in and out and moving the top is a real possibility with the right force. Use a smaller piece of plywood (say 24 round) and construction adhesive to secure the quartz top then use good wood screws to secure to the base.

You need a custom steel support that incorporates 1/4” steel plate with support flanges under the whole. Gravity will not be your friend when it gets knocked off Center and crushes someone's foot.

My friend did this for her kitchen table using the left over marble. Her round marble top was larger as it is 48" round.

I was contemplating doing a base for my dining table and there are loads of bases available. I also googled tulip Saarinen bases replicas etc. and lots came up.

In terms of fabricating, that wasn't an issue for my friend as it is attached somewhat to the underside. I've sat and leaned on the table for years and it's completely secure.

What is problematic is glass on top of a base because there is no way to secure the glass to the base. That's why I ultimately decided to not go with a glass topped dining table as I wanted something more secure if anyone leaned on it heavily.

Look st local restaurant supply houses also. Not loving the X base support for the larger tables shown, but for a 30”, in engineered stone, it’s probably OK. I wouldn’t do natural stone with it though, and I’m surprised they sell it that way, with such a lack of support.

Thanks to everyone who answered my question. The Room and Board base is interesting, but I worry about the fact that it is not secured to the table top. Since I posted my question, I've actually found something that might be the answer. I would need to glue a piece of plywood to the quartz top, as suggested above, but it looks like it would be easier to secure. Here's the link:

https://www.etsy.com/ca/listing/601693510/tulip-round-table-round-table-base-table?ref=shop_home_feat_2

I think the problem is that you have a mismatch between form and function:

- A banquette needs a center-foot table (such as the one you're suggesting) so that people can scootch around to the back without interference from the table legs.

- A quartz tabletop will be very heavy, and it needs multiple legs to support it.

How to do this? Could you order a thinner quartz for the tabletop? Could you go with a quartz lazy susan in the middle of the table instead of a whole tabletop? Could you make the table rectangular so you could attach one side to the wall /one leg on the opposite side? Sorry, that's all I've got, and I don't think it's much ... but do consider safety.

The one you posted on Etsy is a cheap Chinese knockoff. I would still be quite nervous about putting a heavy top on it even if you adhere it to a plywood base.

There are many potential buyers on R&B who questioned ask about not having it secured. And there are many buyers who said it doesn't matter. The reviews are good. I love the base. It is one piece and not a two part knockdown that would weaken where connected. I toyed with a quartz top but ultimately decided on using a maple wood top that I painted (went with a modern pencil edge that complimented the base). Easy peasy to secure. If you head into a Williams Sonoma or Crate and Barrel many of their current marble tables use the concept of a wood underlayment secured by construction adhesive to the marble. I looked like a fool examining it in the store, but I didn't care.

I would like to thank Aurora Tee for telling me about the Room and Board Aria table base. I ended going with that and it has worked out really well. My quartz table top is only 30 inches in diameter and 3/4 inch thick, so the weight is not an issue. I didn't line it with a wood either. The people who installed my counter tops and sold me the table top put a blob of silicone at the center of the X and it seemed to do the trick.