Quote from FM_Tarwater:
Look into mini-prime accounts, or at least someone who can provide clearing and a DVP capability. Keep in mind you need an account size somewhere in the neighborhood of a million bucks to really even be considered by the smallest of the mini-primes.
As far leverage is concerned, I'm unsure the rule of thumb for corporates, but I know for muni's an estimate is 8-to-1 for short term hold periods.
As far as prop is concerned, the more sophisticated shops trade bonds. But unless you are a prop level quality trader with asset class experience and P/L history, it's very unlikely they will talk to you. Keep in mind I'm talking about the true prop firms, not the chop shops where you show up with $5,000 and they provide leverage.