Buy the XRCD version of Jazz at the Pawnshop. This is one of the best sounding CDs I have ever heard and it is very close to the lp version. It has an astounding sense of immediacy, even though it may be a tad bass shy. And while I have never heard the HDCD version I cannot imagine that it can get much closer to the lp.
Also, the XRCD version has more flexibility as it will play on any cd player. Think about the future when you upgrade, your new cdp may not have the HDCD decoding chip in it.