If you're interest is in keeping the very clear, uncolored presentation, that Tele's typically produce; you'd best retain either them or Siemens.
Personally: even the very slight increase in, "warmth" of the early 60's Amperex Navy 6922, dissuaded me from choosing it over the early 60's, grey shield, Siemens CCa.
The (same generation/construction) gold pin, Siemens E88CC, E188CC, etc, has the same sonic signature as your Tele, or my CCa.
I currently have Two early 60's Siemens gold pin, grey shield E88CCs, two E188CCs and two CCas in my BAT VK-D5 and am enjoying the same very clean, uncolored sound as with the six CCa Siemens, I removed to compare. Those are now my backups.
There's a reason for their popularity and (now) their scarcity.
I've bought tubes from the following eBay purveyor, a number of times and found him knowledgeable, honest and dependable:
He has a few NOS Teles and Siemens, of the 6922/E88CC family, toward the bottom of the second page.
Regarding the Russian tubes that became so popular: It was obvious to me, a decade back, the cream of the crop were confined to just a very few years, the supply was largely exhausted and I MISSED IT. Thus: no opinion.
The following may be of interest:
and:
https://www.tubemuseum.org/ProductDetails.asp?ProductCode=SH%5FCCa%5Fsingle