My BHF is my BFF !
I have one form 12/51 with the metal knob and glass lens
I had to take it all apart for a good deep cleaning when I got it (Paid 99 cents), It's like new now and I shoot 4 or 5 rolls a year. Mine easily accepts 120 film in the supply side with a 620 spool on the take up. I develop my own B&W and C-41 so as to not risk losing that 620 spool.
Of course there is a Flickr Group dedicated to the Brownie Hawkeye Flash: http://www.flickr.com/groups/browniehawkeyeflash/
Ha! I see you've already found it, Christopher!