IMO, if you are going with 8' interior doors, you are trying to make a statement. I would go with nothing less than a stain grade 6 panel solid wood door.

Almost all commercial wood doors have a particle board interior with veneer "skins". https://www.vtindustries.com/architectural-doors/ is one manufacturer. The veneers are usually thin.

Take a look at TruStile. They have gorgeous doors in both MDF and wood, but not your desired MDF + wood veneer. Not sure why you're looking for such an obscure item. Seems odd to me.

I think the term you are looking for is composit or less expensive wood core with high quility veneer. Yes there are many options and imo,better choice for interior doors. 8 foot solid core doors are h-e-a-v-y and can shake the walls and chop fingers off when slamed. Your choices will be limited in raised panel unless you have them custom built. Try and find a local door manufacture where $ can go into quility instead of shipping. Your builder,trim carpenter and/or cabinet maker should be able to answer these questions,why haven't they?

Yes. Today, many if not most "wood" doors are veneer over a variety of stable cores, some MDF, some finger jointed lumber, etc. Huge improvement in stability.

An 8’ slab door MUST be veneer over composite. Or full composite. or full something other than wood. Unless you like banana shaped doors that never seal, and stick in summer. Wood is hygroscopic. An 8’ solid wood door could easily be 8’ 1/2” in summer and 7’ 11 1/2” in winter.

An 8’ solid wood door could easily be 8’ 1/2” in summer and 7’ 11 1/2” in winter.

A properly constructed paneled solid wood door is not going to move anything close to that. Flat sawn white oak has a dimensional change coefficient across the grain of 0.00369. That means if you have a 5% MC swing (which is way high for a home) you will see a total change of less than a 1/4" assuming a cumulative rail heights of 12".

In other words your door is likely going to go from 7'11 7/8" to 8'0 1/8". Wood is incredibly stable longitudinally, so the height of the bottom and top rails and width of the left and right stiles are really all that matter. Of course, if you are looking at slab doors my response would be different...

To the OP, yes people make veneered doors, but the more edge profiles your door has, the less sense it makes to veneer it. Just like cabinets many doors will have veneered panels and wood rails and stiles as that is pretty easy to do. Slab doors will almost always be veneered and some simple craftsman styles are also mostly veneered. However, once you start adding in lots of rails and stiles, veneering starts making less sense, it just isn't worth the effort to do all that edge banding.

Thanks for all the comments and help. I did find a site that offers good prices on 8' wood doors. Looking at the Pine. I'm looking at Door Clearance Center in Houston TX. Their shipping is very reasonable. These are probably better prices, even with shipping than I can find in Louisville KY area. https://www.doorclearancecenter.com/8-foot-doors/?orderby=price&shppp=-1

Anyone heard of Door Clearance Center? Looking for reviews. My builder is planning to call them. Other suggestions to look for good pricing on wood doors? This is all new and when you don't know anything about the building side, it can be daunting.

Honestly I have been in the construction supply business for 35 plus years and personally would never even consider for 3 seconds ordering millwork like doors and windows online.

If you want cheap doors, reduce the ceiling height.