I understand there is no specific room temperature recommended for bubs room, but i don't have a sleeping suit suitable for the upcoming winter temperatures. My baby moves around in the cot so I want to avoid blankets. Is it ok to have an oscillating heater in the room with ceiling fan on winter setting to circulate the warm air? I assume the heater should not be blowing directly on the cot. Thanks

You are correct, there is no specific room temperature recommended for baby to sleep in.
Red Nose recommends dressing baby according to the room temperature.
Red Nose has a number of suggestions for dressing baby. Sleeping bags are just one option.
How old is your baby?

Blankets may not be suitable once baby is active & rolling as baby often does not stay under covers.

You can use a heater, preferably one that has a thermostat to prevent room becoming too hot. This can be used with or without a fan - not blowing directly over baby.
You can also add extra layers of clothing as necessary. Ensure baby’s head/face remain uncovered.

“Dress baby for sleep using layers as you would dress or use layers yourself: to be comfortable, neither too hot nor too cold - add/remove lightweight blankets to ensure baby’s tummy or back feels comfortably warm to the touch
A good way to check your baby’s temperature is to feel their tummy or back which should feel warm (don’t worry if their hands and feet feel cool, this is normal).”
https://rednose.org.au/article/how-much-bedding-does-baby-need
https://rednose.org.au/article/how-to-dress-baby-for-sleep