Are Replacements Available for the ARC LS5 MKII Motorized Control Pot and Board?

I recently picked up an LS5 MKII. It has not been modified. I found a few issues that the seller didn't mention. I didn't question this as I paid very little and I really enjoy restoring old gear, any kind.

I have replaced all the electros, obtained 10 NOS Amperex 6DJ8 tubes from Brent Jessee, and replaced the output caps with 3.3 uf Vcap ODAMs. I am burning all this in right now. The sound is great!

However, there's more left to do. The Source/Monitor function does not work. I replaced the switch (gee, that was hard) but the problem persisted. I haven't done a detailed test of the control board yet. A problem for later as I have a work around right now.

The biggest problem is the motorized volume control. It doesn't work at all. I have the AR remote. The mute function does work, but not the volume control. I talked to Audio Research about this. After thinking a bit, AR said repair would be very expensive as they would have to re-engineer this function since replacement parts are not now available. AR didn't say which. Right now I'm using a Fosi P4 as volume control. I also use a GEQ, so the path is Preamp -> P4 -> GEQ -> Power amp (ML #27). I'd like to use the tape loop for these functions as I've done with the AR LS22.

Ideal would be a direct drop in replacement. I've seen the large variety of motor control pots and boards on Ali Express and eBay. I really would like a cleaner solution.