I get over to the Erie/Meadville area pretty frequently. Any LHS recommendations along the I79 corridor?
Mercer Junction Train Shoppe in Mercer is the closest to Meadville I know. It is right on the Court House Diamond https://mercerjunction.com/ Dave Minarik has a neat fully detailed O gauge layout in the shop, and he will let you run engines you are considering buying on the layout. It is definitely worth the trip only a few miles south of Meadville.
I mentioned on the first page CT McCormick Hardware Store in Zelienople, a little farther south right off I-79 at 147 S. Main St. http://www.cttrains.com/ Jeff caries on his dad's tradition of offering a great line of O gauge trains in his full service hardware store. It is a step back in time, as is all of Downtown Zelienople. He has a ton of stuff stored upstairs he will bring down if you don't see it in the store. I find he offers great prices to order what he doesn't have in stock.
If you want to travel as far as Cranberry Township (PA Rt 228 - Mars Exit) less than a mile off I-79, there is Hobby Express as George G3750 mentioned. https://www.hobbyexpressinc.com/ They don't have a lot of trains on the Website, but they have a full line of O gauge, HO, N, Large scale trains. Their showcase is full of great locomotives from Lionel, MTH, and some Atlas I think. If you do go as far as south as Cranberry Township, you can hop on the Pennsylvania Turnpike to get back to Ohio quickly.
I can't find it here on the Forum, but I know someone up Erie way has mentioned The Train Shop 3310 Buffalo Rd, Erie, PA 16510 (814) 790-4887. I have never been there. I don't see a Website, and Google says it is Temporarily Closed. I do not know if that is because Erie County was the only county in Western Pennsylvania to not move forward to the Green Phase of COVID-19 or not.
I hope you can stop in one or some of these shops in the near future.