Getting a high CD socket weapon would better then a high DPS weapon. Run the numbers in the AH, and an EF would greatly boost your DPS numbers AND APS.
Double LS is not necessary, the LS/LoH route is perfectly viable too, especially with 1.07 round the corner.
I am not sure why you when for that Litany if you are looking to break 150k dps. There are plenty of rares out there that can perform better, also your nats isnt the greatest ever. Avg dmg is worth alot when you have high APS, check my profile out in d3up.com, removing those avg dmg modifiers would reduce my dps by 10k each!
I recall you got it for 200M, I think you should be able to resell it for that value after tax, maybe even getting a small profit.
A rare with 30-60 avg dmg, 75 dex, 9IAS, 4.5CC, 50 AR would outperfom your Litany by 10k dps. Likewise, getting 25-50 avg dmg, 8IAS, 4 CC on your Nats ring would increase your DPS by 10k. Those are actually quite affordable for your massive budget, round 250M will get you one including 1 defensive modifier (vit/%life/30-40 sec resist), but you have too look around. 10k at our level is really alot!
As you can see, my weapons are markedly inferior from what you are looking at, yet I am already at 175k dps unbuffed. A better OH if I could get LoH elsewhere would put me nearer to 185k dps, a WH + crit Mempo would easily allow me to break 200k dps.
I would suggest a crit EF with 1200+ dps, and a LS/LoH, 60 CD, OH with 900+ dps, preferably with good dex. Along with those rings I suggested, you can easily get 175k DPS.
Get a crit mempo/good WH and you can hit 200k DPS.
Get your weapons asap and we can do some runs sometime!