Please advise Famicom replacement AV/PSU board.

[Volo]

Hello dudes and dudettes!

I recently got my hands on a genuine Famicom. Thing is awesome, but RF video is annoying. I wish for a clean AV mod, which shall make it as usable as a modern famiclone.

I'm considering Power VAMP PSU board, but I find it expensive and lacking in features. Let me list the features I want (in brackets I'll note whether Power VAMP has the desired feature):

• Rectifier for PSU polarity omnivory (✅);
• No modification of console shell (✅);
• Cost of under 35$ - I don't want the board to be more expensive than the original Famicom cost to me (✅);
• PWM voltage regulator (❌x - Power VAMP has "toasty" linear LM7805);
• Pre-amplified Composite Video (❌ - Power VAMP does not amplify composite);
• Pre-amplified Stereo mod (❌);
• Hardware stereo/mono switch (❌).

Could you point me to a board, which shall fulfill most of my desires? I know NESRGB has most of the features, but the price tag of US$120 is beyond my budget.

If there is no such board, perhaps I should design it? I mean, all of the above features are well-documented - the Bill of Materials should be under $15-20.

[Volo]

UPD. I found something like I want made by evgenykzz2.
Sold for peanuts.
Sadly no Stereo and I don't like ruining the Vanilla aesthetics:



Can you advice a better option?