Looks very much like a stock Yamaha one with replaced lines. They came stock on several models including some of the early non US fzr600s, here' a poor pic of the one that came on my 89 fzr600.
You will need to get that big hollow union nut thing you can see in the middle of mine to hold it on(part 7 below). If you using the older cartridge style filter the rest just bolts straight down onto the cooler housing, If your using the spin on filter type you will need to remove ~3mm so that the top of the nut doesn't protrude past the rest of the housing.
This is from an 88 fz600
1 4K0-13461-01-00 PLATE, ADAPTOR
2 2H9-13493-00-00 PLUNGER
3 90501-12413-00 SPRING, COMPRESSION
4 90209-06173-00 WASHER, SPECL SHAPE
5 99009-17500-00 CIRCLIP
6 93210-87723-00 O-RING
7 90401-20089-00 BOLT, UNION
8 90201-25526-00 WASHER, PLATE (T2.0)
9 2AX-13464-00-00 HOSE, OIL
10 2AX-13465-00-00 HOSE, OIL
11 93210-10197-00 O-RING
12 91316-06016-00 BOLT
13 3KM-13470-00-00 OIL COOLER ASSEMBLY
14 90480-12475-00 GROMMET
15 90387-060A7-00 COLLAR
16 90209-06174-00 WASHER
17 95826-06020-00 BOLT, FLANGE
18 90480-16284-00 GROMMET
19 90462-10066-00 CLAMP
20 90462-12140-00 CLAMP
21 90387-07598-00 COLLAR
22 91316-06025-00 BOLT
23 95311-06600-00 NUT