5 Speed--bad news?

["Allan & Kathryn Weidenheimer" <allanw@domain.elided>]

After disassembly of my 5 speed, I found the mainshaft fifth
speed gear, P/N 238613R3, looks bad on the teeth where the
synchro slides onto it.  This part is, of course, unique to the
overdrive 5 speed.  The direct units have a different part number.

So, anyone have a lead on a source for this part?  I plan to try
Active Gear in Seattle tomorrow on my way to the airport.  My 
synchos are bad too, but I already have new ones from Active.
If I can't obtain this part, then overdrive for my tranny will not last
much longer.  I think the parts to make it a direct drive unit (t-36)
are available, but that would defeat the reason I have it.

So, does anyone have an Advance Adaptors catalog?  Do they
make anything that would allow an NV-4500 to bolt to the IHC
bellhousing, or an adaptor from the block to another brand 
bellhousing?

Thanks,
Allan Weidenheimer
72 1210 Pickup