tube friendly monitors...unfortunately on a bookshelf. suggestions to narrow search?

Hello.  I didn't see a recent discussion that covered both tube-friendly and bookshelf friendly speakers.  I am looking for any friendly advice or suggestions for a starting point to limit the search.  Unfortunately, office space demands that the speakers be placed on bookshelf, about 4-5 feet apart.  I suppose rear-ported should be avoided, so that is limiting.  Here goes:

--budget is variable.  it's an office with necessarily poor placement, so probably don't want to go nuts.  maybe 500-2000.  used in good condition is fine, and they don't have to be particularly "pretty."

--25"x25" openings with 12" shelves, but the bottom is 22."  So, can extend slightly beyond the sides and top, but will have several inches at the bottom--can't bring them to the edge.  10x12 room.

--driven by Cary CAD120Smkii.

--mostly listening within five feet at low to moderate volume.

--can add a sub and active crossover.

--would prefer decent detail, with some warmth. 

--avoiding metal drivers, this time around.

--for the space, mostly classic rock, classical, and jazz.


Have Polk Lsim703s there, now, on auralex pads, with 24x24x4 acoustic panel behind them.  I like them, but not sure how tube and bookshelf friendly they are.

Thinking something along the lines of VA Haydn Grand SE.

Any suggestions for the search?

Thank you.