Sorry to hear about your mast. Bed news indeed, because the cost of the mast often exceeds the cost of the boat itself. Yes, D&R (Rudy) sells masts, and yes he's still kicking as far as I know, but he's always been slow to respond in the summer. IIRC, Rudy charges $1100 for a mast, but the "killer" is the shipping. It has to be crated and then shipped commercial, so expect another thousand++ dollars. The mast is truly the "Achilles Heel" of our otherwise very cheap and modifiable daysailers.
All is not lost, however. Any Daysailer mast will fit in any other (so a DS1 mast will go in a DS2, etc). Depending very much on where you live, you can go get the mast yourself, just trailer your boat over to it and pick it up. I highly don't reccomend driving any distance with an empty boat trailer, they are way too light on their own.. Anyway, if you are anywhere within in a day's drive of southern Mass (Assonet, Ma), go pick up a mast direct from Rudy. Otherwise, you are probably better off buying the cheapest "project" DS you can get your hands on and then parting it out, this one is in Minneapolis:
https://forum.daysailer.org/forum/viewtopic.php?f=17&t=6946#p42081(And you may even like a DS1 better).
Good luck!