Does someone manufacture a replacement gear set for MDC HO Pennsy Atlantics to give a higher top speed?

Loco in question was manufactured in the 1970’s and has the “double reduction” gear set. Its scale top speed is more like that of a Shay than an Atlantic.

You should be able to regear it with no problem.
Here’s a start:http://search.yahoo.com/search?p=HO%20locomotive%20gears

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