You might try the Kimber female RCA's. They are built nice and they are fairly slim. Kimber sales male and female connectors, capacitors, wire and a lot of other stuff along with WBT.
RCA Females, chassis mount
I need to replace the RCA input jacks on the rear of my power amp. (Audiolab 8000P). the unit has any array of 4 (2 top 2 below)with minimal clearance around them, so need some with minimum diameter to allow clearance between RCA's. I have looked at Cardas CTFA's, and these might work if outer clearance(incl outer diameter on nut)is 1/2 inch max. I have 9/16 center on center between RCA's. Any candidates other than the Cardas that might be slimmer? (looked at WBT and these look bigger (size, and cost).