Im classic lover and playing mostly all classic servers exist in the market.
You can buy classic files 2.0 for 5.000e PTS (like gamecoast.com)
You can buy 2.5 files 2.5 for 30.000e PTS (Like danieldefo.ru)
You can make a good L2J Server like L2Classic.club (2.5)
But for sure if you want quality for above 2.5 chronicles you need to put much money and work.
You have few options. You can buy for 90.000e Classic Kamael PTS.
You can buy L2Scripts and work for 1 year to have playable files.
You can buy L2Mobius and work for 1 year to have playable files.
Or you can try to buy from the only 1 advanced private shards wich are working hard
(i dont think they will sell you)
- L2Lionna/Pandorra, etc. (join l2lionna is online to see their files)
- or l2remorse (wich has i dont know from where thez got now very very good files you can ask acces to their test sever in discord or forum)
thats all options you have. good luck classic is a hard territory