The marking means that it is a 10kohm 1 turn precision potentiometer. It would normally look like a normal type potentiometer but with an encapsulated plastic body (usually grey) a bit under an inch in diameter and the body about 1/2 inch long. The shaft will be 1/4 inch dia. with the screwed bit 3/8 inch dia.
If this sounds like the right thing then you will need to get it from a specialist electronic component supplier and all they likely need is the 6187 R10k L1.0 designation and whether the one you have has mechanical stops in it or not.
These things are not your regular el cheapo pot 1 dollar job (I think they are around the equivalent of USD20 here) so I think if the dealer says he will do it for USD40 I would go with that myself to be sure of getting the exact correct thing in case of variances in the position of the mechanical stops, etc. But if want to do it yourself these guys may be able to help -
BI Technologies Corporation
4200 Bonita Place
Fullerton, CA 92835-1053
Customer
Service - (714) 447-2345
Fax - (714) 447-2400
They make them (but I think elsewhere as they are an
english owned company) but that is their US office.
John