Keyed Lever Deadbolt Latch Set, 3 inch Screw Centers 1-1/2" Backset - Satin Chrome
The original manufacturer does not provide a warranty on hardware. ( out of business)

Application: Primarily sun rooms and four Season Enclosures with aluminum doors
Hardware Type: Surface mount with tubular latches
Backset: 1-1/2 inch

Best Replacement Option:
P2000-35SPL, Single Point lock, 1-3/8" Backset + New Handle Set ( several options)
( Lock Case Depth: 2 inch, 2-1/8 from faceplate )
The P2000 option is the most expensive, and may require a little more work, but it provides the best results.

Other Options: Storm Door Hardware ( none are ideal )
305036 with 1-5/16" backset is extremely close to covering existing holes. Door thickness may be an issue!
306211 with 1-7/16" backset Should cover existing holes. Door thickness WILL be an issue!
( Will need longer Cylinder Tail Piece, Spindle and Screws)
303098 with 1-3/16" backset is extremely close to covering existing hole - comes with Plates

ADDITIONAL INFORMATION ON ORIGINAL LOCK SET
The most common point of failure is the latch mechanism.
Mortise storm door handle hardware kit with 1-1/2 inch back set in satin chrome.
This kit includes combination spring latch with deadbolt.
Lever Projection, Inside: 1-3/8 inch from surface to inside
Lever Projection, Outside: 1-1/2 inch from surface to inside
Door Thickness: 1-5/8 Inch
Exterior Faceplate Length: 3 Inch
Exterior Faceplate Width: 1-3/8 Inch
Interior Faceplate Length: 5-3/4 Inch
Interior Faceplate Width: 1-13/16 Inch
Interior Handle PZ: 3 Inch
Interior Handle Screw Hole Center: 4-3/4 Inch (4 Holes at 1-3/4 Inch)
Key Housing Length: 2-1/2 Inch
Key Housing Width: 1-3/8 Inch
Keying: Rekeyable American Cylinder Dexter - Kwikset
Deadbolt Backset: 1-1/2 Inch
Spring Latch Backset: 1-1/2 Inch
Spindle Type: Square
Spindle Diameter: 1/4 Inch
Spindle Length: 5-1/16 Inch
Finishes: Satin Chrome only, Polished Brass discontinued.
Contents: 1 Inside Handle, 1 Outside Handle, 1 Lock Cylinder, 2 Keys, 1 Deadbolt, 1 Spring Latch, 1 Spindle, 12 Screws, 2 Keys