When you see SALT as them if there is an opitunity group near you/special playgroup, you need to get a referal from a GP,HV or SALT.
PECS is easier with 2 people but it is possible to do with one, at playgroup we use 2 people but at home i do it on my own (my dh isn't keen on helping as he hasn't excepted dd's possible ASD).
To start with sit at a table with him at snack time, give him an empy plate, lay 3 pictures out infront of him (say apple, banana and orange), to start with put the fruit next to the pictures so he can see clearly what the pictures meen, next say 'ds, what would you like to eat', use his finger and point to each picture saying what they are 'apple, banana or orange', let him look at the pictures, whilst making him point look for any kind or reaction (a sound, a long stare at a paticular photo or a clear point), if you get any kind or reaction for a picture then take that as his choice, point his finger on to the choice and say 'I want ', give him the fruit.
When you get the chance to have another person with you, get him to hand you the photo by the other person putting it in his hand and physicly make him pass it too you. With dd we only needed the 2nd person a couple times as she picked it up within 2 days. If you get stuck finding another person you can put it in his hand and make him pass it too you but it is easier with 2 people and less confussing for your ds.
I can see this maybe hard with a small baby, maybe plan snack time around babys nap. I find it hard when dd1 is home from school but now she just joins in with dd2 and thinks its one big game.
At first it can take up alot of time, now dd keeps bringing me her photo of 'crisps' expecting food in return.
You could also just make him up a little book of photo's to get him used to pointing at them and getting a reply from you. Maybe a picture of you, dp/dh, baby,his drink cup, his bed/cot, your house and any pets. Just leeve the book where he can get it so he can flick through or bring it to you when ever he likes.
How long have you been waiting for SALT and portage?