For those that are curious, when replacing a Volvo 120SE saildrive on a Volvo MD22L, not only does one need the new core 130 saildrive, you will also need mounting and adapting hardware.
So far, this includes:
a new clutch/ adapter plate (3581526) $489.11
spline sleeve shaft (3843112) $305.24
cover plate/ mounting kit for under the boat will probably need to be replaced (22303438) $122.50
Total $916.85 at volvopentastore.com (with free shipping).
I'm pretty sure there will be a new prop at some point and anodes as well.