Bought my parents one when I was in High School 20 years ago for $70 (that was a lot back then), and its still in their front yard between their front walkway and the front door of their house. Its grown beautifully and both they and I think back about when I gave it to them as a 16 year old, back when I worked as a landscaper in the summers. Here is a link that might be useful: Still into it...but now its landscape lighting!

Japanese maples grown in a container in your zone must be overwintered in a protected location. That means a garage, unheated basement, greenhouse, etc. Just wrapping the pot is insufficient protection - temperatures that drop below around 26F can fatally damage the root system. Otherwise, a lot of Japanese maples should do well in your zone in the ground - zone 5 is generally considered the lower cut-off for these trees but location and/or microclimate can extend that. Look at whatever JM's are available in your area - otherwise, check out some good JM's for colder climates, like in the attached link. Here is a link that might be useful: JM's for a cold climate

There's no guarantee the seedling will maintain the same characteristics as the parent, but you might as well give it a try.

Ken, every retail nursery in my area sells Japanese maples; some with a very wide selection and others with less but very popular varieties. The nursery I am associated with sells a big variety, probably in the range of 150 different cultivars. But all the small, young trees - the 1G size, sell in the price range I outlined. I know this personally as this is the size I focus on myself for my collection :-) I get 'em small and grow them on in containers! Obviously, older and larger trees go for a higher price. And variegated ones or those with unusual coloring tend to be higher priced as they grow much more slowly on average and you are paying for the time and care provided by the grower until the tree is marketed. I recall an Oridono Nishiki in a large (48"?) box for sale at a prior nursery I was associated with that was a large mature tree........maybe 10' tall and with a good sized canopy - that was priced at $1800. So yes, they can be expensive for larger trees but you are paying for the size and age. The smaller, younger trees are still very affordable for those willing to be patient :-) In your link, they offered a 7G Autumn Moon (24-30") for somewhere around $225, which is not an outrageous price. I bought mine as a 1G for less than $50 (probably a lot less......that was 15 years ago or longer!) and today it is 7' tall and equally as wide. The point I was trying to make is that here in the PNW where these trees of all varieties are plentiful, they do not have to be overly expensive if you start small. And there is really no need for any mail order either unless one is looking for a very uncommon variety. Most better nurseries carry an impressive selection.