Since you are on budget , maybe you can try to DIY, using wood patty? you can find them in Home fix. jus fill up the crack and varnish a little will do. But if you looking for a perfect repair, likely a professional has to come in to remove the cracked pc and select to the most matching color of your mature wood. That will cost you around $80 per pc not including transport and labour. Having said that, it not advisable to remove any pc of parquet cos they are joint by tongue & groove , so you have to ensure proper maintenance over the area repaired. If not over time tat pc will come loose too.