Tonearm for Technics SP-15

my friend has a unit in a plinth with a dust-cover. it looks like OEM Technics to me, I could check. Grace arm is in a circular removable board, also looks OEM, with a long oval cutout for various lengths.

removable arm board looks like this

(seller says fits 9 or 12 sme arms

That one looks like an SME cutout. Several arms use that mounting- it allows the arm to be moved to get the right geometry.

Yes, I have an SME 3009, sliding plate, but no VTA on the FLY.

I found a GST-1 just listed in New Zealand, sliding plate with VTA on the Fly, and magnetic anti-skate

I'm pretty sure it will fit his SP15 Plinth, would need to confirm the rear length and height.

seems to be a good price

just for the record, both technics EPA-100 and EPA-250 are 235mm + 15mm overhang = 250mm effective length, the maximum length for the SP15 OEM bases.

that's 9-7/8" effective length.

I have a Technics SP-15 



good tonearm.

I want to thank all audiogon members who posted advice and recommendations.  I learned a lot and finally placed an order on a technics a fully loaded lightly EPA-a250 on a B500 base kit.  Separately, I found a base panel for the B500 that was made for my technics SH-15b3 base cabinet/plinth.  All should arrive in the next week or two and once I set up I will report again.  Thanks again!!