OK here is my obligatory Glock speech
Glocks are legal in MA
Dealers are not supposed to sell you a new one
There are creative ways to get one, that involves buying it in pieces, then filing a eFA-10 within 7 days of it being able to fire a shot.
There is the used at gun shop market
then there are private party sales that you will find here on NES.
Do not pay stupid money for a $600 dollar gun.
I like Glocks, in NH used there isn't a used one in a FTF sale that has sold for more than MSRP if still in stock configuration
Tons of them in the 475 dollar range... Gen3 Glocks that are really nice guns
There is no reason to pay stupid money for a polymer pistol, as I said great guns at MSRP or less, more than MSRP there are much better guns out there for the money.
G17? What are you using it for?
The G17 is a brick, and if you are using crippled magazines ( we'll have the discussion about buying over priced 30 year old magazines that the plastic is turning to crap later) then you are carrying a lot more weight than you have to for an incremental increase in grip area and sight radius
Anything in the Sig P365 line is going to be dollar for dollar a better buy IMHO in MA unless you find someone selling for what they are going for in a "free state" like NH, FL, etc.