I jungle Lee Sin semi-regularly but I still haven't found a build I absolutely like. I checked guides on multiple sites, none of which worked for my play style.

Stuff you'd want to know, I have AD Marks/ Quints, Armor Reds, MR Yellows, and 21/9/0 masteries. (I absolutely love the clear speed in 21/9/0, I can often get a Smiteless blue and get the other team's red level 2.)

Anyway, builds I'm playing around with right now are Wriggle's Lanturn > Giant's Belt > Frozen Mallet/ Warmog's Armor > some more tanky items as needed (Hexdrinker?). (Games don't often last long enough for me to get a full build.) I definitely like building tanky, but both Warmog's and Mallet are very expensive, and this hurts my mid-game damage output.

What would you suggest?

tl;dr: Tanky jungle Lee Sin build with 21/9/0 Masteries?

MMMMM i would go 9/21 masterys if tanking gives you alot of tankiness anyways for boots i usually ger mercs unless they have 1 ap and 4 ad's or a very fed AD carry then a wriggles>sunfire>mogs for some suggestions cause atm Health is OP

Don't rush frozen mallet. Get the wriggles, boots (mercs/ninja defedpending on team comp's CC), Phage (utilize the slow early compared to giant's belts larger health gain. As a ganker you will be in 2v1 situations and not the focus of damage since they will be trying to retreat) After that I would see how the game is going to play out. If your lanes are getting pretty fed, focus on building tanky damage mid game and more damage items late (building some damage/resist combo items and a triforce). If the game is not looking so good, focus on going very tanky mid game and just use the high utility in your skills to keep your team alive during fights.

That's alot of health with very little utility, damage or defenses. I'd stick with just Mallet or just Mogs.
I don't like Hexdrinker/Maw on anyone.