I have an older Kenmore - probably 30 yrs old, & it is a workhorse! Very heavy, takes anything I sew - I've made backpacks, hubby's suits, winter coats, upholstered furniture, made draperies, wedding dresses, you name it. Ebay has many old, sturdy working machines, but I'd try locally first - maybe an ad in local paper.
I also use a Babylock Quilter's Choice (won the grand opening prize at LQS), & I like the variety of stitches it offers.
My next hunt is for a Singer 15-91 - just cannot beat the old Singers & wish I had Mom's old machine. I'm even considering a treadle machine - not that I actually need it!
Good luck with your search - please post a followup & let us know what you decide.