Thanks guys, that's very helpful! And a very interesting note on the tin foil there Detlef. Glad to hear I snagged up a good one and an oldie.
I think given that bit of history I will leave those bits of adhesive in place and simply repair the crack in the way Jeff suggests and give the blade itself a light clean just to remove any active rust.
I'm not sure how to go about replacing the rattan since I've never done this before, but maybe I'll do that in the not too distant future. If anyone knows of a good tutorial (video is probably the easiest to learn from in lieu of knowing someone with actual experience personally) that would be very helpful.
Should the scabbard wood be oiled, and if so, what would you recommend?