I have just purchased a Borascope from Aldi for £60 and has a colour screen , one meter long flexi approx 10 mm wide with built in internal Led lights at camera end , comes with a few hook attachments but you could adapt your own or use in conjunction with a three claw grabber .
Just had a though " how about using suction if you can locate it in the tank"
Use a fuel pump to suck it out ?
Good luck Austerwobbler