I was thinking you could feedback the output of the opto back into the input led - thus when it turns on it 'locks-on' (still no "off").

Yeah - really a simple 7400 based toggle will work (which flip-flops exactly, since
there are so many...).

I sense the author has NO IDEA what we are talking about... also.

 

OP, can you use stripboard?

 

OP, can you use stripboard?

Also known as Vero board.

 

I sense the author has NO IDEA what we are talking about... also.

Indeed

Okay so there are no commercial available flip flops or DIY kits?

 

Not ready built that I know of. Do you have a friend with a bit of electronics knowledge? Might be the best bet.

 

Well not really, but I do a bit about soldering etc (I have build a few amplifers etc) but I need a kit or at least a BOM
Its just that if I have to buy parts etc in different places (Farnell, Mouser etc dont ship to private people here in Denmark) shipping of single parts can become very! expensive, hence I wanted a kit or a ready made version