Where can i find..

a collector with a max dmg hammer with dmg mod 15%

I don't think theres a collector that gives hammers.

And if there is, it probably won't be max damage.

well in that case neone wanna sell a 15% max dmg one >50 for a cheap price :-D

There are a couple of of max damage hammers in the desert, I don't know what the damage mod is on them though.
http://www.guildwarsguru.com/forum/s...0&postcount=76

Cheap and 15>50 really shouldn't go in the same sentence. But, if you want a cheap 13>50 one, I have one.
http://www.guildwarsguru.com/forum/s...ad.php?t=53354

IIRC, the collectors in the desert offer the Max Dmg Hammer +15% damage while enchanted and the Max Dmg Hammer +15% while in a stance. I'm pretty sure there is no collector that offers Max Dmg Hammer 15>50 or 15<50.

I don't think there are any collector's max weapons that are 15>50 or 20<15, they're mainly stance or enchant as far as I know. If they offered 15<50 I wouldn't take that anyway as it wouldn't be max

There are 15>50 collector bows.