In the version I sing Allan it's

"I'll sell my rod, I'll sell my reel
I'll sell my only spinning wheel
for to by my love a sword of steel
Suil, Suil, Suil a Ruin etc etc"

i think the significance allan may be in the time the song was written. This would have been a time without supermarkets, designer clothes shops etc. The food you ate you grew/caught yourself. Your clothes you made yourself. So she was willing to go without food and clothes to protect her lover by giving him a sword of steel. I'm not sure of the significance of rock. it's not in my version. It may be to do with her rocky land or home which she also sells. The land in the west of ireland is poor and rocky.

Any it's only my opinion right or wrong

Mj