$20 a piece is $580
$35 a piece is $1015
$725 is the median of the high/low values
These will appeal to mostly traditional bow-hunters who also like and want to read; that's a narrow market for a 29-book collection. Even those who do like and want to read may not necessarily want to read all of what's in the collection. Also, I would guess that most of these readers already have the majority of the titles that they want in their collection which they've picked up along the way over time.
I'd guess that unless you find the just right collector, your probably looking at $550-700 shipped. I could be off in value, but these numbers seem reasonable to me.