Many have mentioned a repair tape they keep in their tool box for emergency repairs of things like hyd hose, fuel line etc. Don't remember and can't find in search of "repair tape" what the brand nam...
I have had good luck repairing plastics using Shoo Goo reinforced with fabric. I have used it with woven FG cloth and used a tongue depressor to wet out the cloth with the Shoo Goo. Goop would work also. I have also just used old bed sheets where strength was not important. Just sand area well wipe with acetone or alcohol and put one or 2 strips to cover the crack, let it cure overnight or until it gets hard before you use it.