Difficulties in parts search?

Parts list

Difficulties in parts search?

	Description	OEM Part #	Price
1	1 816626A20 Key switch assembly	816626A20	US $247.07
2	2 90468A1 New Genuine Part	90468A1	US $4.45
3	3 76424 New Genuine Part	76424	US $13.68
4	4 55422 Stud, , control panel to boat	55422	US $5.79
5	5 24676 Washer, , control panel stud	24676	US $1.28
6	6 68219 Nut, stainless steel	68219	US $2.54
7	7 816479 New Genuine Part	816479	US $39.89
	replacement
7	7 816479A3 Plate kit-mount	816479A3	US $39.89
8	8 88107 Key switch	88107	US $76.02
	replacement
8	8 88107A5 Switch Kit Key	88107A5	US $76.02
9	9 93543 Nut, key switch	93543	US $5.46
	replacement
9	9 879755 Nut, special - black nylon	879755	US $5.46
10	10 90311 Insert	90311	US $1.50
11	11 816492A1 New Genuine Part (NEW DESIGN)	816492A1	US $64.10
	replacement
11	11 8M3001068 Alarm Assembly Audio Warning (NEW DESIGN)	8M3001068	—
11	11 68878A6 New Genuine Part OLD DESIGN	68878A6	—
12	12 68879 New Genuine Part OLD DESIGN	68879	US $5.26
13	13 8127111 Spacer	8127111	US $3.71
13	13 812711 Spacer	812711	US $3.71
NI	NI 894911 New Genuine Part	894911	US $5.49
NI	NI 894912 New Genuine Part	894912	US $5.49
NI	NI 894913 New Genuine Part	894913	US $5.49
NI	NI 894914 Key 1d 2	894914	US $5.49
NI	NI 894915 Key 1e 2	894915	US $5.49
NI	NI 894916 Key-1f 2	894916	US $5.49
NI	NI 894917 Key-2a 2	894917	US $5.49
NI	NI 894918 Key 2b 2	894918	US $5.49
NI	NI 894919 Key-2c 2	894919	US $5.49
NI	NI 8949110 New Genuine Part	8949110	US $5.49
NI	NI 8949111 New Genuine Part	8949111	US $5.49
NI	NI 8949112 KEY Ignition (2F)	8949112	from US $5.49

Key Switch Assembly Diagram Mercury-Mercruiser 250 18260415-946683