You'll find that there are many good 19.5 tires available. Toyo, Bridgestone, Cooper, Double Coin, etc.,etc.. Where I get my tires these days is from Amazon. I'm a prime member and the tires are shipped free, than I have them installed at a Love's tire shop at their truck stop shop.
Here's how to compare sizes:
Compare Tire SizesAmazon has a Double Coin in the size you mention for under $200:
245/70R19.5Over 13 years of full timing, I've used several different brands and they've all been good. Probably because they've been commercial truck tires not specific RV tires. I don't care for the Michelin tire line because they're just too soft I guess, and start developing sidewall cracking very quickly. None of the Toyo's, Double Coin, or Bridgestone truck tires, (and now Roadlux 22.5 on my current bus) I've ever bought have had excessive sidewall cracking.