Try this link http://www.mountainmaples.com/trees.php
Use the tree finder feature. Select red for summer color and then under 6 feet for landscape size.
It should give you 3 choices although there may be more options for containers or if you consider more uncommon or new cultivars not on that website. I would suggest a low grafted red dragon without staking but it would be pushing 4 feet hard in 10-15 years I would think.

Another thing to consider is how much width do you have to work with? Crimson queens are often 2-3 times as wide as they are high.

You might also research Red Pygmy- Linearilobum group(red narrow, straplike divided leaves)

maybe 'red filigree lace'. mine has been extremely slow-growing in a container so get the largest one you can afford.
it is a beautiful plant, though, and the leaves are as finely-cut and delicate looking as any i have seen.

Here is a link that might be useful: 'red filigree lace' link

I would shy away from most dissectum JM varieties as they tend to grow wider than tall. Look for some dwarf varieties with an upright form. Here are some red varieties that might work, although they still might need judicious pruning to keep within 4' wide:

-- Atrolinear
-- Pixie
-- Shaina
-- Beni hoshi
-- Red Pygmy
-- Lion Heart (upright dissectum)
-- Beni komachi

There are many dwarf green-leafed varieties that could work, and some of them have red leaves in spring (and fall) but turn green in summer:

-- Kamagata
-- Mikawa yatsubusa
-- Ojishi
-- Shindeshogo

Actually, I have plenty of width, ten feet or so; it is the height I am concerned about as I don't want it to cover a window. Thank you for all the great suggestions.

Sorry, I misunderstood your message. There are many dwarf red Japanese maples that you could easily keep under 4 feet -- Crimson Queen, Red Dragon, Orangeola, Red Filagree Lace, Beni ubi gohan. All of these will grow wider than tall. Crimson Queen is the old standard for red dissectums and should be easy to find in your area. I have a CQ that I bought about 18 years ago, and it is still only about 3' tall, although it's probably 6' wide. It would be wider but I have it planted near my house where it can only spread in two directions. CQ and Red Dragon will keep their red color all summer long if they get enough sunlight, but Orangeola will gradually turn green. All have red leaves in the fall. Stay away from Garnet, it grows quickly and will get much taller than 4'. Also look for a tree with a low graft rather than grafted to a tall stem (the mushroom look), as that will help you keep the height within your parameters.

This is just what I needed to know, Dawgie. What about Tamukeyama? Can it be kept to four feet?

Tamukeyama would be harder to keep under 4' tall compared to the other varieties I listed. It can grow as tall as 10' or more.