When rebuilding engine, change everything otherwise its not worth doing. so:
sump gasket
front crank seal
rear crank seal
oil pump/front seal carrier gasket
rear crank seal carrier gasket
pick up pipe gasket
head gasket
manifold gaskets
valve stem seals
cam cover gasket
cam seals
cam belt, tensioner and the two guide pulleys
waterpump and gasket
And finally make sure you use a good quality oil and filter. if keeping 2.0 oil pump you will need a cvh oil filter other wise it will hit the chassis leg.
To expand on what onslack said about the gearboxes, as you go further down you lose acceration but gain top end
1.1 box
1.6 si box
1.8 xr2i box
1.6 xr2i box
rs1800/rst box
diesel gearbox
or escort rst series2 box will bolt straight on, has same ratios, about, as rs boxes but with added bonus of LSD
Adjustable lower arms.... i made mine myself, got some ok ish lemforder ones from my work, drilled out the rivets for balljoints, dilled the holes out so they where slightly longer and used a bolt and double nutted it. works a treat, no stupid amounts camber.
Might not have rosejoints in them but can allways get some polybushes pressed in. And its easier ot change ball joint when it goes.
Edit, where abouts are you from?