Intralipid 20% is a good enough alternative, just remember that in some countries (and even in our paediatric hospital until very recently) the fat emulsion of choice is/was intralipid 20%. Just proceed with the same precautions you would use with all lipids and same monitoring requirements (consult PI for max rate of infusion etc).
I completely agree with previous recommendations of using Omegaven 10% in babies reliant on long term PN if the shortage of SMOF continues.