Ummm... the auction I was at a couple weeks ago where they almost gave away some of those.  I know, big help, huh? First a warning.  You mentioned it but I'll reinforce it, the DB420 you linked on ebay won't work for your freq's.   The tricky thing to watch for is some antennas are close.  For instance the DB224 you referred to has 6 different configurations.  There is a DB224-E on eham.net ( http://www.eham.net/classifieds/detail/288283 ) but it is 130 - 150 mhz.   I don't know if it would work on your frequencies. I'm away from my desk.  I'm going to post this then go find some information and come back and edit.

OK, Places to look include the Radio Information Board ( http://www.radioinfoboard.com ) eham.net ( http://www.eham.net/classifieds/ ) and QRZ.com ( http://forums.qrz.com/forumdisplay.php?f=7 ). I think you'll have to register to take full advantage of any of them.  The QRZ pages move quickly, kind of like on here.  Just remember, they are amateur radio forums, not commercial.  Some equipment will cross over, some will not.  A lot of things have top end freq's of 150.

Back when I was dealing with cell phones and a bit of two-way I bought quite a bit from Tessco.  They give a $725 list for a DB224. ( http://www.tessco.com/products/displayProducts.do?groupId=340&s... ) I don't know what their purchasing requirements are these days, it's been over 15 years since I bought from them (I guess they have been around a while!)

I don't have a clue on cost, but Comprod has an interesting looking folded dipole antenna. See photos of a tower top install at http://wadsworthsales.com/kb9icomprodrepeaterantenna.aspx

See http://wadsworthsales.com/comprodantennas.aspx for more info

Another site you might want to visit is repeater-builder  ( http://www.repeater-builder.com/rbtip/ ).  Of particular interst might be their antenna page ( http://www.repeater-builder.com/antenna/ant-sys-index.html ) and suppliers page ( http://www.repeater-builder.com/rbtip/supplyindex.html).  Just remember, their focus is on amateur and while basics do not change, some of the details may not be quite correct for your application.

Here is a quote from the antenna page you might enjoy:

Repeater owners have favorite antennas - some prefer colinear antennas ("fiberglass sticks"), others prefer dipole arrays. Personally I prefer grounded dipole arrays. Colinear antenas are more prone to duplex noise (see the "crackling" article below), dipole arrays can have phasing harness degredation. Picture four loop dipoles side mounted on a steel mast. Suddenly one day you notice that the coverage has gone to hell. When you check the antenna with a SWR bridge you discover that you still have a 1:1 SWR. Phasing is the key concept here. The RF is fed to the dipoles by means of a cable harness of critical-length coaxial lines that accomplish both the phasing of the dipoles and RF power division. The VERTICAL pattern of the antenna is determined partly by the RF phase relationship between the dipoles. When the antenna is new, the phase relationships are perfect. As the antenna ages, moisture can infiltrate the coax and connectors. Coax dielectric can begin to deteriorate. This will slowly cause the vertical pattern (and gain) of the antenna to change. A perfect SWR does you no good when your RF power is going straight up in the air or straight down into the ground! So if you use a dipole array then you want to be an annoying perfectionist about the phasing harness.