I waited for 6 months for my local dealer to get a 642 no lock. Then one day he called having took in a minty used one that I bought. He still never got any from Smith, going on 8 months.
I put in a request for one w/o the lock, new or used, at one of local LGS six months ago. I never heard back from them.
I found out that the Gander Mountain in my area are expecting to get some 642's this week, but I strongly suspect they will all have the locks. They are selling them for $449 but with a $50 mail in rebate the price is actually $399.
Kind of pricey, but I may have to break down if I want one, as I can't find any in my area regardless whether they have locks or not.