There are many new bows that can still be relaxed in the field with just an allen wrench. First is the obvious one since they advertise it... Newberry. There are also several models of Martins you can still relax in the field.

It is simple to find out if you can get away with relaxing your bow with the limb bolts. First put the bow in a press and remove the strings and cables. Relax the press. Now, back out the limb bolts until they come out. Now thread the bolts back in two complete turns. Next, try and put your strings and cables on. If they go on easily you can safely disassemble your bow without a press.