Hi,the filter kit (SKU.1877) has adapter rings(67mm/72mm/77mm/82mm) and separate 49mm/52mm/55mm/58mm/62mm adapter rings to sell,it can fit if your lens size is included. 

Since the Olympus e520 is a Four Thirds sensor this adapter will NOT work with it. It is made for Micro 4/3 sensors, not 4/3. 

Could you please update us your full Minolta lens model ?as Minolta has MD MC and AF mount, K&F Concept MD-M4/3 is suitable for: Lens: Minolta MD MC Mount lens(not for Minolta AF mount: KF06.157) Camera: Micro 4/3 (MFT) mount mirrorless camera like Olympus PEN, OM-D series, Panasonic Lumix DMC-G1, G2, G3, G10, GX1, GH1, GH2, GF1, GF2, GF3, GF5, GH4, Panasonic AG-AF100 Mirrorless Digital Cameras, Black Magic Pocket Cinema Camera (BMPCC) 

your lens curvature will require an adapter for any filter system. I saw the Lee filter adapter for this lens...but it seems it does not fit all filter holders. Lee filters will work with the adapter. 

No, it's just the filter with case. But any brand of 100mm square filter holder kit will work (Lee, Kase, Nisi, Tiffen, etc) which accept 2mm thick glass filters. I have Kase one.