Gripen might be a stopgap, but it is an older platform. At least with updates it's at least considered a "4.5" generation fighter. F35 is pretty much the best option atm.
Planning ahead though, Canada needs to get involved with either GCAP (Global Combat Air Platform or FCAS (Future Combat Air System).
We can't realistically pull off another Avro Arrow with modern 5th/6th generation features by ourselves. We can partner with more reliable allies though, and help bolster our own defence aerospace industry at the same time. In either GCAP or FCAS, we would be the junior partner though.