For a 1st hand report on installing an SME 309 tonearm on an SL1200 MkII (using the SME armboard from Sound Hi Fi of England), go here at TonePublications' website and download Issue 22 as a pdf file. Jeff Dorgay, the editor, used the armboard to install a used SME 309 for around $900. The result of the experience is that the SL1200 + SME 309 became his his new reference for turntables at that price point.
I have an SL1210 M5G. Someday ... someday ...
I have an SL1210 M5G. Someday ... someday ...