Alternative to electrical chocblock

It depends how much space you have.

Minimum space solution is crimps, you can heatshrink each and then heatshrink the whole lot.

Easiest is probably Wago connectors but these (like choc block) should really be in a box.

There are now small 'in line' boxes suitable for a choc block connectors, e.g. :-

Search for an in-line mains cable connector. They are available in both permanently wired types, and plug and socket types - you want the permanently wired type.

Choc boxes are not suitable for this - they have exposed live parts (albeit not very exposed) and no cable grip.

When you extend the cable, make sure you fit a 3 amp (or lower) fuse in the plug. (Short cables of this type are allowed a higher fuse rating than longer cables.)

If the clock currently has a molded on plug, you can't reuse that. Make sure you remove the fuse from it and dispose of it such that children can't find it and play with it. One child has been killed by doing this.

Wago connectors are the industry standard now, but maybe not appropriate in this case. Why not just have a short extension lead with a socket?

Thanks for all the advice guys i did buy a couple of the ebay/dragons den ones, but they are not great quality so i went for the one Andre suggested, and i got a couple of 2 wire and a couple of 3 wire, I'm sure the rest will come in handy, many thanks again guys.

Jim