More than the stage cost. Unless you're happy with a Chinese 24 position switch and a dial display.
Easiest way to do it would be a set of two pin pcb sockets on flying leads. Then just screw different caps in. Or build in a pair of 4ca sockets just for cap loading. That's an easy job
Do you want to mess about repeatedly or find the best value for a specific cart?
Kuzma Stabi/S 12", (LP12-bastard) DC motor and optical tacho psu, Benz LP, Paradise (phonostage). MB-Pro, Brooklyn dac and psu, Bruno Putzeys balanced pre, mod86p dual mono amps, Yamaha NS1000m