Cheapest bike lights?

[Don Pablo]

Once a week I need to make a 5 minute cycle in the dark. Previously I have taped hand-held flashlights on, but that is time consuming and wasteful (tape-wise).

Does anyone have a recommendation for some front and rear (maybe side too) bike lights? I’m looking at about €20 maximum for an entire set, due to only needing them for a few minutes once a week, but you can try upsell me if you want.

I intend to keep them out of the rain, and use rechargeable AA or AAA batteries.
I want them to be the “Be Seen” kind, as I already have a headlamp I can wear “for seeing”. Ideally, they should blink at a moderate hertz, but that’s not a deal breaker.

If “adaptors” exist for mounting AA hand-held flashlights to the bike frame, that would work for my purposes too. 

Thanks.

[hiraethus]

Twofish lockblock for the front - velcro clamp attachment so you can use whatever you've already got.

Aldi/Lidl/Wilko/whatever for a COB usb rechargeable rear. Go for Cateye/moon/lezyne if you're feeling flush.

[ThundahBeagle]

Bell Radian 350. A set of those goes for $25-$30US. 3 LED lights per unit, one front unit white light, one back unit red light. They have a blink or pulse feature and have done well by me for years. They attach to your handle bars or other piping by way of an integral "C" clamp that connects using the included Allen key.

[Don Pablo]

Thank you for the advice, hiraethus and Thundah. 
I like the two fish lock block mount idea best, I’ll try to get my hands on some of them.