You can always refinish a set of stairs....so long as they maintain code. That is to say the rise is maintained from the bottom step (the basement) through to the top step (the main floor with vinyl).

I'm going to point something out: Stairs are EXPENSIVE. They are SOOOO expensive that they can cost MORE than an entire level worth of flooring material.

If you go with the wood, you will be disrupting the rise heights. That means you might bring your stairs 'out of code' and that gets EXPENSIVE to fix. To get the wood in place, you will need Finishing Carpenter. These guys are the MOST EXPENSIVE/SKILLED guys who swing a hammer. Like $150/hr type of cost.

Now imagine buying wood treads for $50 piece. Now you add in the cost of removing the current tread and installing the new treads (possibly having to trim the stringers). Excellent. Now you have to sand...sand...sand...etc. Do that on each step/tread. Now you have to finish it. The cost of the finish and stain will add another $5/tread (and the rental of the palm sanders/sanding machine). You have just spent $60/tread onto your bill.

If you stairs risers need to be 'jigged' to keep your stairs to code, you are adding in another $150/hour for the Finishing Carpenter. While he's there, he will just go ahead and do the sanding/finishing. Now your 'cheaper' wood treads will cost you $120/tread or more.

Or you go with the manufactured vinyl treads/risers and have NO ISSUE with code...because the rise will not have changed.

I know it hurts to spend $90/tread (assuming you have roughly 10 - 15 dreads) can cost $900 - $1450 just for the materials. But that is PEANUTS compared to the cost of a Finishing Carpenter.

Or you simply put carpet back on the stairs and live with the look.

Wow, what an amazing response!!! You taught me so much! I do have one broken tread and some of the other treads may need repair. This house was built in 1974 and the material used was cheap (like plywood cheap I've been told)... But my handyman says he can repair steps -- and I feel confident that he could install the vinyl treads (heck I could probably do it myself as I've watched a ton of videos -- but I'm in my 60s and don't think physically I could do it...