Welcome to the Forum!

Sorry to have delayed answering for a couple of days but my weekend is Tues and Wed.

If it's only an aesthetic issue, and you can live with it while you use the pool, waiting until you close to address the tile/ plaster is a GREAT idea! Why loose a week of using the pool when you can have the repairs done during the 'off season'?

As for SWCGs - the Jandy and Hayward models you gave are both good units and will do what you want. Please remember that they are sized for a 40,000 gallon pool, running 100% 24/7 - this would mean that you'd have to run your pump almost 24/7 to generate enough chlorine (the Hayward will produce 1.45 lbs of chlorine in 24 hrs, which is equivalent to 1 gal of 12.5% liquid chlorine - IIRC) Of course your chlorine demand might not require you to run the unit 24/7 and you can always supplement with bleach.

There are others here who know the chemistry better than I, if I've misrepresented something, I'm sure they will correct me

If you have further questions, please ask them.