On that motor you can use Liqui Moly 5W30, the long life one in the purple bottle. It'll also be around R500, but contact Moranor as I think he will be cheaper. You need 6.3 L of oil.
Autostyle are idiots, it's a flat filter you need. Get this from the agents. I put more faith in the cotton at the bottom of the filter than hoping for K&N to do the same job. It's pricey but only needs to be done in another 15k km after this.
Pull the CIA report on the car and check if the fuel filter was changed in the last 50k km or so. If not, replace it else just leave it as its a kak job.
If you don't have cash for the Microfilter now, you can just blow it out and do at the next 7500km oil service. Generally these get changed every 30k km, or when real dirty.
Get a size 27 socket to remove the housing of the oil filter.
On average I spend around R2500 on a 'full' service doing it myself, agents only parts except for the oil.
I flushed my engine using LM engine flush, do this at your own risk though.