Sovtek KT88 - Russian made, cheap
EH KT88 - same as Sovtek AFAIK
Gold Lion RI - Russian-made but different than Sovtek
JJ KT88 - Czech-made, cheap and failure issues with some but allegedly good tone
JJ Blue Glass KT88 - allegedly same as regular JJ but with blue glass
Mullard KT88 RI - Russian-made, don't know if same as Sovtek/EH
Telefunken KT88 RI - made by JJ, don't know if same as JJ KT88
SED/Winged C KT88 - Russian-made in old Svetlana factory, well liked similar to other SEDs, no longer made and getting $$$
The Shuguangs are where it gets interesting:
Shuguang KT88-98 - three-hole plates, no side getters, allegedly pretty good, lots of rebrands
Penta Labs KT88SC - Chinese-made, solid plates, triple (dual-side) getters, allegedly better than KT88-98, also some rebrands
KT88-Z Black Treasures - Look very similar to KT88-98 but with a coating on the glass (looks smoked), allegedly awesome but ~$110 ea.
TAD KT88-STR - Allegedly China-made, 3-hole plates like KT88-98 but different. Base looks different, looks like there's at least one side getter.
Jolida KT88-98 - Same as Shug KT88-98
Valve Arts KT88 - Same as KT88-98
Ruby KT88STR - Same as KT88-98
Ruby KT88VSTR - Same as Penta Labs SC
Tubestore Preferred Series KT88 - Same as Penta Labs SC