Help! - tube complement advice - SFS 40

Hello. I recently acquired a Sonic Frontiers SFS 40. It is my very first tube amplifier. It will probably be powering a pair of B&W 805’s, but I need to break in this amp and engage in some in-home listening room demo sessions before any final decisions. I am looking for advice on good “new” or “new old stock” tube complements fitting within a $300 budget. I am open to either tube complements based on the stock EL34/6DJ8 setup, or any of the optional tube complements. This includes 6CA7’s or 6550/6550A/KT88/KT90/KT99a types, and ECC88, 6922 or 7308/E188CC designations for the i/o. The amplifier did come with (2) complete tube complements. I have no idea how many hours are on any of these tubes. I have the original matched pairs of Gold Aero EL34’s. I also have matched pairs of Svetlana EL34’s, they appear to be Svetlana’s “Mullard” copies. I have (2) of the original (4) Gold Aero 6DJ8’s. I also have a matched pair of Sovtek 6922’s. Additionally, I have (4) mystery i/o tubes. The manufacturer appears to be Russian; but as I do not read Russian, I just don’t know. They are all in their original packages; (3) unopened, (1) open, probably for inspection. I’m also assuming zero hours on any of them. Anyhow, in addition to advice on a fresh set, any advice on the tubes I do have would also be greatly appreciated. More later on those mystery tubes after I get a translator involved. Thanks.