Hello Gidget01,
Welcome to the forum.
Basically the RI-3 and the R-85 uses the same power supply, boards, there is diffences in the keyboard and the display board but the rest of the boards work in the same fashion (the RI-3 because of its size, can't display 200 titles so they put a diode in the pricing board so you could not select 8 or 9 as a third digit if you remove this diode marked as RI-3 it will play all 200 selections).
If you require testing/repairs on your boards, there are a couple of companies in the USA that people use for there Rowe Ami repairs or you could send them to me in the UK.
Regards
Alan
Alan Hood
ami-man
UK