Port-Oak aged Porter plans

I've been thinking about making a port-oak cask matured porter for a while; obviously not to actually age it in a cask but will add port-soaked oak chips. Denise likes Old Tom brewed by Robinsons which has a port flavour.

Here's my plan anyway:
12 oz black patent malt
4oz chocolate malt
4oz roast barley
8oz crystal malt
2 teaspoons gypsum
4kg light spray malt
2oz Saaz hops
1/2 oz Hallertau hops
1 teaspoon Irish Moss
1lb black treacle
6oz oak chips
half pint port
The Hallertau hops have a real blackcurrenty aroma too which should go well. We've still got plenty of oak logs left from a tree taken down, so I'll make some shavings and sterliize them in the oven. I think porters work better made with light malt and then darkened and flavoured with the speciality grains rather than using some dark or amber malt. I've not used treacle before but saw a clone recipe for Theakston's Old Peculiar which used it so thought I'd give it a go; I think 1lb treacle should be the equivalent to 1/2lb sugar which should add about 0.66%ABV to the final brew. A quick calculation means that the beer should end up at about 8%. I've ordered the ingredients from my favourite brew shop in Northwich - Phil at Brew2Bottle.