I'm going to say congratulations. You may not feel it, but a positive spin is better than negative. I still run but not nearly as much or fast. Age and pain, 60 years old, is putting me on a bike more than running. Just a few observations that made me feel better and I hope work for you:
1. I can buy helmets, tires and such and not be spending more than I did on shoes and running gear. A great set of tires cost less than a pair of running shoes and I had to change those out every 3 months.
2. There is no rule you can't have several helmets just like you might have had with your running shoes.
3. We love to go fast under our own steam and bikes are a lot faster than running. I've registered for a duathlon in Mississippi and am looking forward to it. Also, I'm starting to ride with some folks from the gym who are training for a century. I'm looking at it the same way I did my first marathon. Let me suggest joining, supporting and riding with you local club.
It is addicting and once you make the adjustment, just as fun and a lot less pain.
Post a follow up and let me know how it goes on the bike search.