a cheaper alternative would be wvyernhide armor, i believe you can find it for around 60-150pp depending on the piece and seller. If you find yourself having trouble soloing, quick fix would be to buy a set so you can farm easier (since it's still a big upgrade over soft leather) and then re-sell it later to make back most of your money.
Damask is another alternative, it's dropped so most likely to see people trying to auction it off before vendoring it, if you get lucky maybe you can get it at vendor price. It's not quite as good as imphide, but less expensive.
Tmaps are also a great chance, if i remember right most levels have 2-3 pieces of leather you'd find useful. You might even get lucky and be able to tag along on some VE/E maps, there are a lot of 65s who still need the quest items, can probably box and do it themselves but would probably be happy to see some of the loot not rot, have someone to talk to, and/or speed it up a little.
Silk-Woven band is also nice for monks, probably cost you 700-1k but comes with a clickie 6slot 100% weight reduce bag. Item itself has nice stats and is low weight.
Not a soft leather slot, but the newport gate necklace would be an upgrade over yours and give you a gate. You should be able to solo for heads off greatpaws pretty easily (they should be teal), probably even archpaws (blue) at a slower rate while getting some xp. If you box a healer, you should definitely be fine to duo it.
Amice of the golden dawn would also be a nice upgrade (if you got some other haste item) that you should be able to do some xping while getting quest drops if you box a healer. Another shoulder upgrade would drop from reclouse in mielB (probably need a healer for this also) and it comes with a clickie invis.
And finally since you are 57, Treak drops a nice headband (33% haste), a clickie no weight bag. Pounders drop an 18sta/50hp wrist, and some sleeves that are an upgrade.
