Options for resurrecting VAX 4000/400 and Vaxstation 3200

Dear all, I have two VAXen that I'd like to resurrect simply for the sake of playing around with The Real Thing[tm] running VMS. Note that I'm completely new to VMS and DEC hardware -- hence the interest! Box #1 is a VAX4000 model 400 with no working CPU (KA-675) and 2x 32Mb RAM, an RF72 (wiped), plus a KZQSA QBUS controller. PSU is good, fans squeal on startup but run silently once spun up. Have VMS installation media in CD. I have two KA-675s for this beast: Board #1 (originally installed) has a failed B-cache (console reports SUBTEST_35_12, DE_B_Cache_diag_mode.LIS) and crashes with an asynchronous write memory failure when booting VMS from CD. Board #2 (DOA from eBay but fully refunded) has a dead DSSI bus 0 controller and crashes on SHOW DEV; I assume that's a write-off. Any chance of identifying the flaky B-cache SRAM on board #1 and replacing it? Alternatively, anyone out there have a KA-675 for sale? Box #2 is a VAXstation 3200 with TK50, and an RD54. PSU and fans ok (and very quiet), ditto CPU. The RD54 is unformatted; I understand this can only be formatted in the field with a VS2000 or with some obscure field diagnostics. There's no SCSI controller, so I can't install from CD. I haven't been able to track down VMS installation media on TK50, and I doubt they'd still be readable anyway. On top of that I have no idea what condition the drive is in, as I have no blank tapes to test with. I've found tape images online but see no way to dump these to TK50 (assuming the drive is ok), unless I get a TZ30. What are my options and chances of success for getting either of these boxes up and running with VMS? A KA-675 and TZ30 can be obtained from resellers, but I hesitate to invest several hundred in something this old purely for the occasional mucking about. I have also considered selling the units (or parts thereof) if nothing gives. Any ideas much appreciated, --GT -- "END OF LINE" [MCP, 1982] "... nowhere in the standards is it specified that 'programs that use a lot of memory may randomly crash at any time for no apparent reason'" [Stackoverflow forum, 2012]