Venox 250i (EFI) need operational fuel pump

[kbosak]

Hi,
after several trials to fix the problem by pro mechanic,
after cleaning fuel lines, I still have idling problem and occasional 'delayed rpm and uneven acceleration' problem when the weather is hot and the engine is very hot.
The problem is worse at high temperatures, less problematic when fuel tank is full.
Opening the tank is not stopping the rough idle when engine is hot.
One mechanic disconnected fuel lines from fuel pump and said that at first place, the pump is developing unreliable and low pressure.

So it looks a fuel pump. Now the problem is I cannot even find part number, yet alone a pump for sale. As I understand it is mounted inside fuel tank itself, but all the schematics I have do have only elements I would say are typical for earlier carburetor version. Unless I don't understand something.

For example here:
https://kymcopartsonline.com/catalog/search_diagram_detail.php?s_fk_manufacturers_id=21&s_fk_model_year_id=1&s_fk_scooter_model_id=31&s_parts_diagram_id=842
I see 37800-KED9-900 Fuel Unit. Is this the fuel pump?

EDIT: This looks like fuel level metering unit.
Either in section canister:
https://www.kymcopartsmonster.com/oemparts/a/kym/5b50e76187a866110c2e0873/canister

Then fuel pump would be 
17310-KED9-M30 (but I think this is a carbon-filled filter for gas tank venting)
or
1880A-KHD8-91A (AI/C-AICV ASSY but some searches indicate it is secondary air filer? omg&wtf?)
or
https://www.kymcopartsmonster.com/oemparts/a/kym/5b51e77787a8660d78cad49a/fuel-tank
1695A-KED9-900 (AUTO COCK ASSY FUEL - but this look some ass-designed valve not a pump)

I am lost.