I noticed there is a few buck tags for unit 144 leftover but it is privste land only. It is suprising to see leftover buck antelope for this state. As the other 2 said you can do archery or wait a build a few more points. Honestly I dont think Colorado has the trophy caliber antelope (80"+) that equates to the number of points it would take to kill a big buck (hope that made sense). That being said a friend of mine killed a 79" buck on a OTC archery tag a few years ago. I have 6 points and am assuming I will draw the unit I want next year for a rifle tag. This unit has potential of 85" bucks but I would have to be extremely lucky to find one.
If your really itchin to hunt antelope soon I would check out Wyoming.
Jeff