[Chris Burkard]

No there is no replacement that will fit properly other than the original.

You have three choices:

1) Locate an original style motor on the internet - New/Old Stock - this is becoming harder to find - put the part number in your search engine and start dialing for dollars. I guarantee that someone has one, it is just a matter of finding it.
2) Purchase and install the new replacement motor and have a fiberglass specialist grind out and refinish a relief pocket in the dash for the new motor to fit into so the window will close all the way (this is what most 38 owners end up doing). This just requires a fiberglass and gel-coat specialist so that it looks factory when it is complete. If you try to grind it out and you are not skilled in fiberglass and gel-coat, it will look like a hack job when it is complete.
3) take your old motor to an electric motor specialist such as a starter/alternator rebuilder. Many times they are able to locate gears and parts you could not hope to find as they specialize in this.

Good luck and let us know how you make out.