Keyboard shortcut during notation entry - repeat previous bar

I did do some searching to see if there was already a way to do this, but I didn't find it.

I'd find it handy to have a keyboard shortcut that's active during notation entry, and possibly only on the first beat, that copies the previous bar. I'm currently doing some part transposition for a community band, and when you're in the low brasses in some marches, you get a lot of two and four bar patterns where it's not really convenient to stop, go back and highlight the previous bar, click copy, click on the new bar and click paste.

Having a hot-key or keyboard shortcut that did that would be handy and cut my transcription time down.

If there's already a way to do this, if someone could point me to a description of it, I'd be very grateful.

Thanks.