You should be fine at that alright tommy, most of the classics mapped are done to 1.3 or 1.35, 3 of the top UK mappers Andy Forrest/Bob Rawle & Pat Herborn all use that boost figure.
Mine has been mapped to 1.3 bar and has been mapped for the last 2yrs without so much as a groan from the engine/turbo so I would imagine its quite safe to boost at that level.