what tubes for my Rouge 99

It depends what sound you are looking for. Any Amperex from the Heerlen, Holland factory will have the widest soundstage, nice mids and sound sweet in a Rogue preamp. Cleartops have excellent high-end extension, are detailed and open.
RCA Blackplates are a different direction to go...warmer, yet very open (a classic NOS tube sound).
I've also tried Siemens, but found them too analytical.
NOS Amperex are expensive and in great demand, RCA are affordable and very high quality.

I am assuming you are talking about 12AU7s. RCA clear tops are abundant and available if you want to get some. I would also ecommend Amperex tubes made in Heerlen Holland (the sought after one is a sub called 7316). If other Amperex are within reach I would try them.

Mswobo-
At the recommendation of the fine folks at Rogue, I upgraded to a pair of RCA clear tops. The first thing that presented itself to me was a pronounced difference in the clarity and extension of the mid-highs and highs over the stock tubes. It was especially noticeable when listening to female vocalists. I bought a pair from them about a year and half ago for and haven't looked back. I would give them a call. Happy listening.
Jerry