If you have a mithril flake to spare you can craft (or ask somebody else to craft) a lvl 65 LI. Add in a Symbol of Celebrimbor (you can trade for that at the skirmish camp) and you can even make it a 2nd age LI. Javelins, Spears and clubs can be crafted by woodworkers, while the other weapons are made by weaponsmiths.
Alternatively, try moving forward a bit (the Bonevales in Dunland should be a place appropriate to your level, although the eastern edges of Mirkwood should be fine, too) and kill humanoids of your level until they drop the LI of your choice.
Lastly, you could check the Auction House or ask your kin members and friends to keep their eyes open for warden legendary weapons. Like I said above, they drop off humanoid mobs (LI level is the same as mob level) frequently.
Yeah the AH is probably the easiest and fastest way to upgrade to a 65 Third Ager.
You really do want to get yourself a pair of 65 Second Agers (javelin + melee) as soon as possible, though. They'll see you through nicely till you're 75 - the javelin especially - and then you can upgrade to a pair of 75SAs. Plus, they're super cheap now and you can get enough marks for all the parts you need just by running a couple skirmishes.
I think you also get a 65SA javelin as a quest reward near the end of the Enedwaith Epic book. You can do that even if you dont have the Enedwaith quest pack - though it might still be faster and cheaper to just have one made, if you'd be starting that Epic book from scratch.
Also, I am pretty sure that there is a barter vendor in Thangulhad (sp?) in Mirkwood that does have level 65 third ages. You do have to be kindred to get them I believe but you said you were kindred so that is not a problem.
I didn´t concern myself too much with legendary weapons untill I was getting close to level cap. I rate everything below level 70 as inferior garbage :P.
Sad but true. While levelling, I pick up a new level appropriate set of LIs every 2-3 levels and decon the old ones as I go along. This means you really shouldn't put too much effort into this gear since it only lasts for a few weeks before getting obsoleted. This isn't the legendary system most would prefer, but it's the one we have. As it stands, the LI game doesn't truly start until level cap, and then it gets reset as soon as the new expansion hits.