Now that you have a vise on the way, you can start playing with your mill. But on a going forward basis, I'd suggest regularly trolling eBay and craigslist for nice equipment and tooling. My favorite category on eBay is 'New-Open Box'. I've made some great deals that way on new merchandise at enviably reduced prices. Sometimes you'll find attachments that need a tweak to work on your machine, so you'll need to fabricate a part or bracket. A win-win because you create a must-do project, and you save some bucks in the process. That's called 'tuition'.
If you find something that looks reasonable, post a link here at H-M. You'll get loads of responses proffered by our seasoned veterans. I have both purchased and walked away from items by seeking the counsel from our experts on this Forum.
Regards
Oh, and P.S.: I agree with the advice to store the swivel attachment. My first mill (used) came with one, which I promptly removed without even asking anybody. That mill is long gone, but the swivel is still on a shelf. I've never used it and am certain I never will. In my opinion, you're better off keeping a lookout for a small rotary table.