As an intellectual exercise (a.k.a.: a way to waste time), I spent some time looking around yesterday and the DC/DC converter -- MER1S0505SC -- seems to be completely unavailable. Octopart has none listed. None at Mouser, DigiKey, Newark, Allied, Jameco, Farnell -- I think I looked everywhere. I even tried a couple of houses that claim to have parts that nobody else has -- still none. Mouser says that 176 will be arriving on 7/26, but apparently that date has already been pushed out a couple of times already.
I also tried looking for a compatible substitute and couldn't find anything.
There may well be a dongle drought for the foreseeable future.
\dmc