See urologist or get scrotal ultrasound first to minimize cost?

M56. I saw my HMO PCP for a painless scrotal mass, and he's pretty sure it's benign, but gave me referrals for an ultrasound ($450) and to see a urologist (maybe $200?) to be sure. Which should I do first if I'm trying to minimize cost given my $7500 deductible? Will a urologist often diagnose obvious issues without an ultrasound, or will they nearly always order one anyway? Will an ultrasound have a diagnosis that my PCP can interpret, or will it always need to be reviewed by a urologist? Thanks!