Lot of data points here.
http://boards.collectors-society.com/ubbthreads.php?ubb=showflat&Number=9690927&fpart=25
It is difficult to estimate sometimes. Being off 3-400 dollars doesn't seem like much but that could be 25% variance.
I like this one better and it went for 1400
http://www.comiclink.com/auctions/item.asp?back=%2FAuctions%2Fallsub%2Easp%3FFocused%3D1%26id%3D1398%26Artist%3DSTEVE%2520DILLON%23Item%5F1152162&id=1152162#detail
I also like this one better and it went for 2400
https://comics.ha.com/itm/original-comic-art/steve-dillon-preacher-29-page-14-original-art-dc-1997-/a/7124-93361.s?ic4=GalleryView-Thumbnail-071515
I would guess 2k. HA seems to get pretty good prices for Preacher Not confident in that assessment though. However, I do not believe these would go for nearly as much on eBay as they did on HA. So , while I am saying 2k, I am also saying I am not sure it would get 2k in another venue.
https://comics.ha.com/itm/original-comic-art/steve-dillon-preacher-32-page-24-original-art-dc-vertigo-1997-/a/7137-93472.s?ic4=GalleryView-Thumbnail-071515
https://comics.ha.com/itm/original-comic-art/steve-dillon-preacher-20-too-much-gun-page-15-original-art-dc-vertigo-1996-/a/121546-13042.s?ic4=GalleryView-Thumbnail-071515