Nice looking table, of course you can't tell about the slates, but I'll bet it will play great.
When I first got married, we moved into a second floor flat. Above our rent was an unfinished attic, very much like this one in configuration.
After asking the landlord if I could use the attic area for a pool table and getting the OK, I purchased an old House Of Lords 9' table. It was built like a brick $hit house.
I put a 3/4 sheet of plywood on the floor to connect the floor joist together for a bit of added stability.
Myself and 3 friends got that table up to the attic. I just want to say, patience, strength, perseverance, and most of all beer.
After it was up there, a few more friends came over, and we swear we could feel the house sway ever so slightly with the weight. But, looking back, maybe it was the beer!
Good Luck .... go for it for sure. 300 dollar tables may be around but that has some nice character. :thumbup: