VTL 7.5iii Tubes

Friend

Contact these folks https://www.tubeworld.com/index_high.htm
at Tube World. They should be able to help.

Mullard 12AU7s are very good tubes and can be just right for certain applications. It sounds as if the former owner had discovered that this tube sounds good in this pre. So why not stay with them.
I like Amperex 7316 tubes which is a straight sub. It turns out that the whole world likes them too, making them very costly. They show up on Ebay... but talk about murky provenance....and they fetch good money any way.
Again if you like the way the Mullards sound go with them. You might want to buy a back up pair from an established vendor.

A friend found Cifte 12AU7 worked best in his VTL 7.5III. My favorite 12xxx is Telefunken ribbed plates. If you have BIG budget, roll Telefunken ecc802s. ~$950 for MP from REPUTABLE dealers.

Ultimately you have to roll and decide for yourself.

Thanks, all. The Mullards sound good, but I hear some tube rush when there is no signal and I turn the volume up to 1/3. Never had that with 6sn7 tubes. Wonder if they are starting to go, although they sound fine.

Thanks for comments. Also am going to ask some pro's, (not that y'all aren't!).

HNY.

Neal