I changed my civics original clutch at 240,000 kms....
yes clutch can get hard.. depends on the manufacturer of the clutch and how its been used.
yes that plastic pin does get broken, bad design on part of suzuki. you can get an exact copy made with steel bolt from a lathe machinist. will last forever.
slave cylinders normally mounted with 2 or 3 bolts. take of the bolts, you should be able to access that pin under the rubber boot. if there is oil inside the rubber boot, your slave cylinder is leaking and preferably be replaced with brand new item. if not, just replace plastic with metal pin. and bolt the cylinder back without opening any pipes.
the first step before replacing any part is the bleeding. check the brake oil and clutch oil reservoir(bottle). I think its the same for this model. suck out all the old dirty oil with a syringe. top up with fresh brake oil. preferably original caltex, siekin etc.
trace the piping. an oil pipe will go to the clutch master cylinder mounted on the engine firewall behind the engine. then another pipe will go from the master cylinder to the slave cylinder. the slave cylinder will have a bleeder bolt on it. normally opens with an 8mm socket. loosen it slightly. oil should start dropping from it. if not, squeeze the clutch pedal VERY little. Do not press it all the way. oil should come out from the slave cylinder.
let the oil come out, the oil in the reservoir bottle will start getting low. top it up, until you see clean oil coming out of the slave cylinder. tighten the bleed bolt until no oil comes. top off the reservoir bottle.
your clutch pedal should feel firm and work properly. drive this way for a few days an observe if this solves your problem.