H-I
I did some research on your Dad's rod and am 99% sure it was built by Horrocks-Ibbotson.
You are correct in that it's not a valuable rod but it was built on a good blank. If it has no hookkeeper and has a snake type stripping guide, with minimal line guides, you can be sure it is a H-I.
No luck on the line weight but I would try a 6 first.
I can certainly understand the rods value to you.
I currently own all of my Dad's tackle as he can longer handle it....he'll be 94 next month.
It holds great sentimental value for me too!
Bob
When you can arrange your affairs to go fishing, forget all the signs, homilies, advice and folklore. JUST GO.