Sorry I just thought you wanted identification . Replacement is dependant on how much you want to spend and how far you want to go . A cheap and very good upgrade is the stepped attenuators on eBay from Taiwan or China and you will notice a very large difference for not too much spend . HiFi Collective have a good range again from medium price around £50 to very expensive . Sorry do not know anyone who could fit one for you .
No problem at all what you are looking for is a 100K Stereo Log Pot . My advice would be to be very sure of the quality and sound of the Volume pot then use HfFi Collective site and pick one like the TKD or Audio Note just view and spending around £50 will get you a very decent quality unit that is not too big so will easily fit where your current pot is .
In my view these are better sounding but they are quite big and you need to have the room to fit one . HiFi Collective also have some that they build to order and I am sure they will be very good too with options to use better quality resistors etc for additional cost.
I fitted one of these to my Audio Innovations Alto, It's a tight squeeze in the Alto, between 2 caps and I didn't want to drill the case to fit a higher quality unit because the Alto is some way down the pecking order among my amplifiers.
The original pot ( 30 years old ) kept losing a channel, hence the need to replace it.
I have to say it doesn't sound any worse than the original and was only the price of a couple of pints.
I didn't use this particular vendor,
there's quite a few sellers of these
I think a pic of the underside is near essential to avoid "issues" here. IS it a stereo pot? Looks like a mono to me, but could be just a compact stereo one? If stereo someone may have drilled the pcb, a consideration for future value. Also what is the distance from pcb to spindle, and what is the diameter of the spindle/screw thread passing through the Fascia, and is the spindle 6mm, 6.3mm, 1/4 inch, slotted, etc. Also what is wrong with the one currently fitted?
Alps seems to have acquired some sort of reputation as being wonderful audio quality components. The standard pots (like the one in the last post) are average at best. They're just an ordinary carbon track pot and very easily bettered.
Checking it just means measuring the resistance across the whole scale and from the sliding contact to each end. What measurement won't tell you is how noisy (and worn) it is.
If it's a decent amplifier/preamp, it's slightly fiddly to fit a decent replacement, as most will need short wire links. Fiddly, maybe, but definitely worthwhile. The Audio Note ones are hard to better at about £50 all in.
I have just replaced the old pot on my Albarry PP2 with a TKD 2CP-601 at around £50 inc. Works very well. I needed 10k, so the Audionote wouldn't do. Also it has pcb pins so might drop straight in, but check shaft length, as it is quite short, but so is the Audionote.