I have never seen a trailer with a chamber/toe adjustment. So If it is out of allignment is is probably due to something bent (axle/tongue) or the axle is mounted crooked (has slipped out of axle keeper on springs).

I would inspect the springs, axle and hitch for damage, tightness or evidence of something out of place before I took it to service. It may be a simple fix. In any case you may get an idea of what you are dealing with.

A trailer axle is alligned with the axle keepers on the springs, that's were I would look first. Check the tongue with a straight edge (perhaps a 4 foot carpenters level) by placing it parallel on the tongue. If there is a gap and the straight edge does not lay flat (check top and sides) against the tounge you will know your tongue is bent. You can also check the axle(s) the same way. We have all seen trailers on the road that have tires bowed out at the bottom and bowed in at the top. Probably due to over load and time (axle bent/bowed). Finally you may also check your wheel hubs for loosness (bearing bad, wheel nut loose). If your hub has movement side to side or up and down you may need new bearing. However, I would think you would have noticed the wheel getting hot or making noise.

Just trying to save you a buck. Like I said, may be an easy fix.