Are you sure you need to purchase a habitat stamp to apply for a preference point? You need to purchase the stamp before they will send you a license; and they encourage you to buy a stamp at the same time as you apply for a license.But I couldn't find anything in their 2008 regulations brochure that requires you to buy the stamp just to apply. The following are direct quotes ob the topic:

PREFERENCE POINT HUNT CODE
You can apply for a preference point without losing points
you already have. A special hunt code is in the hunt code sections
for each species. Entering the preference point hunt
code as a first choice on your application automatically
awards you a point. You also can apply for a license as your
second, third or fourth choice. You must pay the full cost of a
license and meet all license requirements even if you are
applying only for a point. If you only apply for a point, your
money, minus the $3 application fee, is refunded.


HABITAT STAMP REQUIREMENTS

For License Buyers: A Colorado Wildlife Habitat
Stamp is required of people 19-64 who buy hunting
or fishing licenses. With a license purchase, the stamp
is $5 and required with the first 2 licenses bought in a calendar
year ($10 total). The stamp allows access to state wildlife
areas or state trust lands leased by the DOW.

Licenses are NOT mailed until you meet your annual
Colorado Habitat Stamp requirement. To avoid delays in
receiving your license, buy your stamp online, by calling 1-
800-244-5613 or send $5 with each application.


You are encouraged to buy your annual habitat stamp
before or when applying for a limited license. Licenses are
NOT mailed until you meet the annual habitat stamp requirement
(see “Habitat Stamp”). To avoid delays in receiving a
license, buy a habitat stamp online, by calling 1-800-244-
5613 or at a license agent or DOW office. You also can
include $5 for a habitat stamp with your license fee. Put an
“X” in this box if you are sending $5 for the stamp.