Sounds like you have a good plan. Personally if I had to choose between keeping suffolks or lleyns i'd go for the latter. Maybe just my bad experience, but whilst making big thumping lambs, they have a habit of being dumb, slow, hard to lamb, little get up and go and mucky back ends. Still, they do look nice.
For a practical sheep, I think a lleyn is better. As ME says though, most times its more important where you get your sheep, then what breed of sheep, so source from a flock that operates similar to how you wish to. What I want is a ewe who is a good mother and milky, that gives me two lambs each year, off grass, that can be lambed outside, is hardy, got good feet, and whose lambs are tough, quick to get up and suck and stay alive till sold. Well, that's the dream and I don't think i'm a lone. LLeyn wouldn't be a bad place to start.
You should get a half dozen ewe lambs for your £500. But a decent ram of any type will blow your budget out of the water. Your friends advice on Easyrams is good, I assume rather than an 'easy care' ram, he means one from the company easy rams who sell imported newzealand genetics in the form of nz texels, suffolks and suftex's? Never seen one, but they are meant to be good rams, for easy lambing out side on a grass based system.
Sounds very good about getting both equipment and advice from your friend. What does he run ewe wise out of interest?
Maybe it'd be an idea to go to some ewe sales and just see what makes what price etc locally. Don't buy, just watch. This time of year is when the breeding and store sales / shows happen.