John:

If you can't find a suitable style in RTs, as per WienSam's suggestion,
try auditioning some of the regular BIAB files, like maybe C~JCASH.
If you can find one that has the bass part you like, just use the hybrid stylemaker
and move the bass part into the style you're currently using, substituting it for the exsting bass part.
(Did you mean TRAIN style and not trian?).

The other thing you could do is, find a MIDI file on the 'net for Ring Of Fire.
Some have the bass part almost note-for-note to the original J.Cash version.
Open that MIDI file in BIAB, nuke all the parts except the bass, put the bass on
BIABs melody or solo track and set it to play your favourite BIAB bass instrument.

Then mute the Bass button on the BIAB toolbar.

You may have to move some of the MIDI bass notes to line up with the way
you've set up your song. Or you could just use the whole MIDI file, have
BIAB set the chords for you, and then mute ALL the BIAB instruments.

Good luck!
LLOYD S