[Ignatius]

With a T300 ante, there should be T11100 in the pot when it get to you. You are better than 6:1 to have the best hand. Let's consider the alternatives (a typical 4BB raise is assumed for the 1st, all-in for the 2nd raise)
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1) raise-call. The worst alternative. You are a dog over the possible range of hand that will play back in this spot. If they call with overcards, you will suffer negative implied odds on the flop.
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2) raise-fold. If your opponents are as aggressive as described you will rarely take it down but will often fold the best hand if played back.
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3) limp-fold. Same as above, only more so.
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4) fold. You cannot fold when you figure to have the best hand more than 85% of the times, as moving in is guaranteed to be profitable.
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5) limp-call. OK, when it's not raised, but puts you in a bad spot when having to play your 55 for 1/3 of your stack. Best option if you are confident to be able to outplay your opponent most of the time.
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6) limp-reraise all-in. If your stack would have been a tad deeper (say 90k), this might in fact be the best option. With only 75k, a raiser might feel committed too often (esp. if he has you covered) after investing 1/3 or more of the effective stack.
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7) raise all-in. IMO the best play. Your worst case EV is about 6/7*11k+1/7*(1/5*83k-4/5*75k) = 3230 K, your typical EV should be more like 1 BB.