The first thing to do with IO'ing out a MA/Regen scrapper is to build for global recharge. That will make Regen a stronger set (faster recharge means its click powers are up more often and available) and increase MA's damage potential.
If you want to really pimp out the build, then go for some defense as well. In fact, a few defense powers wouldn't be a bad idea, since you can slot in the LotG +recharge IOs in them (though of course these are also very expensive/sought out).
Sets that provide recharge set bonuses:
5-slotted Crushing Impact: +5%
5-slotted Obliteration: +5%
5-slotted Adjusted Targeting: +5%
5-slotted Doctored Wounds: +5%
5-slotted Stupefy: +6.25%
These are the ones that would most likely fit in most builds, though some sets could also make use of 5-slotted Red Fortune in defense powers and 5-slotted Impervious Skin in Resistance powers (both +5%).
You could easily get 25-30% global recharge from set bonuses. Add this to Hasten's +70% and you'll have a good build to work with.
Recharge does help with dull pain and recon. Helps with IH, but I like to build my regens to use IH as a backup power.
Another option, depending on what level you are, is to skip set bonuses and mix and match IO's. Slotting rech/heal IO's from different sets can get you to the ED cap in 4 slots in both heal and rech, compared to needing all 6 for SO's on powers like dull pain.
I went with some rech bonuses, some mix and match, and the thing that helped the most was melee defense bonuses. I use combat jumping, and I slotted touch of death 6 slotted into some attacks. ToD gives i think 3.75% bonus, so stacking it 3 or 4 times really adds up. Obliteration in dragons tail also gives a big bonus. I put the steadfast 3% defense IO into resilience. All those little 3% add up. It really took the edge off the alphas when engaging a mob, and after the big burst is over, it is pretty easy to use the other tools regen has to counter the more steady damage.
Nothing super uber, but it has worked pretty well for me. On a side note, I also put the stupefy chance for knockback into thunderkick. It goes off enough to notice, and acts much like crane kick then. its a good bit of soft mitigation if the knockback doesnt bother you.
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Okay so im looking for lots of rech. I guess now as i think of it, it make more sence.
Hi all. I don't know how to build my MA/Regen at all
does any one have any builds i can look at to get idea from, please don't put the ones with purples and all the fancy stuff i only have a range of 300mil 
Thank for any help you can get me.