Phonostage & Cartridge Upgrade For Rega P5


I am planning for an upgrade for my Rega P5 turntable in near future and would appreciate some advice.

I recently purchased a TT PSU and this added a nice subtle improvement to the P5. The difference is not day and night but for the price paid I have no complaints. I currently have a Denon DL103 cartridge on the P5 and the phonostage is a built-in MC in my Rega Elicit integrated amp. The problem is I am not sure how good the built-in MC phonostage is but from what I gather the quality of it is pretty much crap since it's a low-end unit.

I am curious to know how much improvement that can be had at a modest cost of say $1,000 for both cartridge and phonostage, or possibly just the phonostage alone. Given the quality of the Rega P5, I don't think it is worthwhile to spend a lot on upgrades. I am only concerned on whether I can perceive a *significant* improvement in sound quality with a better phonostage and cartridge and not a small sonic improvement with the TT PSU.

Some good outboard phonostages recommended here are the Dynavector P75Mk2 and EAR 834P. The Rega IOS was claimed to be an excellent unit matched with Apheta MC cartridge but the price is too much for what I am willing to fork out.

Any advice would be appreciated.
ryder
Thanks for all your valuable inputs Ekobesky and Viridian. They were much appreciated and would give me some direction on what to do next to obtain an appreciable sonic difference at a modest cost. I think I'll concentrate more on the phono stage and cartridge optimization. Need to do some reading up on Denon and Cinemags transformers.
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I had a P5/TTPSU/Rega Exact prior to upgrading to my current P7/DV20X-H. I was pleased with the Exact cartridge and have heard the Exact2 is much better. I currently use a Graham Slee Era Gold V phono stage and am quite happy with it too. My preamp (McIntosh C2200)has an onboard tube phono stage but I prefer the sound of my Era Gold V. The GSP is a very simple yet engaging phono stage - sometimes less is better.