Affordable pre-amp solutions??

Hello folks, I am running a Wadia 302 direct to ASL 1009 monos to Sonus Faber Guarneri. I know that running direct I am missing something, mids could be more fleshed out/greater tonal density etc but I can not afford a great pre-amp at this time so I'm wondering if there is something I can use for the short term, that won't hurt the transparency too much but adds some warmth and body.

Somthing under $1k used...some contenders:

Dodd ELP
Eastern Electric tube buffer
Manley Shrimp

Open to other suggestions...TIA.