Ive never had a issue of having the cart pins stretched, or bent improperly inwards due to using a PAR 4n1. Honestly the pcbs on those slide right in with utter ease, just the same as any Capcom or SNK ramcart would, let alone any others. If I was to do the mod, I would charge $50 to do the work. That may be deemed a tad expensive, but I don't enjoy taking apart saturns. Depending on the revision, some of them are more of a pain to do then others on the region mod. You would also have to send a US game disc, and a JP disc also so I could make sure the mod work is solid. I don't keep any Saturn stuff around anymore. The last deck I modded was for Nectarsis, and that was quite awhile back.

Before resorting to me though Id highly suggest hitting up the Sega-16 forums first to see if someone there is willing to do the mod cheaper then me. Explore your options completely is the best advice I can give. Shipping cost for back and forth in the USA is prob going to run you around $30 bucks total as it is, so try to save as much cash as you can.