I once heard that Waltham's Stone watch is one of the very few transparent watches, and they mostly cost over tens of thousands of dollars, which is entirely out of what I can afford.

Since I have been strongly interested in transparent watches because I am obsessed with the inner beauty of the mechanics of a watch, I have been looking for help.

Hopefully I will find the answer here.

Look for New England Watch Co. they made skeleton pocket watch not too pricy

Peter has given good advice and you might find a Shell Oil Company watch given as a premium for buying their products. I believe those were Swiss and sort of see thru.

Dimitry, Colibri produced well detailed, strong running "Skeleton" watches. This one passed through my collection and the same type shows up on eBay fairly regularly.

Is there any other skeletonized watches that are more elaborately finished and still in reasonable price range?

check ebay you might find what you looking for

Here's a late example.