solo and quintet mouthpieces

[Skaman]

Hello Everyone,
I am in need of your opinions.
I currently own 1 tuba, a Willson 3050cc. Its my baby, and I use it for everything.
I use a schilke 67 for all of my playing.
But I have now become more interested in excerpts and more challenging solo repertoire.
I cant afford a bass tuba right now.
Any suggestions of a mouthpiece that may make playing in the high register of a contrabass tuba easier? specifically for brass quintets, some orchestral excerpts and solo rep.