A figment of sheer hype called ""The Jubilee Mysteries"" has been importing a batch of recent minor suspense books from the Commonwealth, including those of Australian Pat Flower, who seems to specialize in the kind of guilt-ridden, claustrophobic domestic tales that Ruth Rendell does so well. This one, sadly short of Down Under local color, closes in tight on Martin Briggs, who pushes wealthy wife Ellie down the stairs (she kept bugging him about getting a better job). Enter lovely, crippled Valerie--ostensibly Ellie's old friend and part heir--to comfort Martin and share her chic boutique with him, but really (and all too obviously) to revenge Ellie's death by nurturing the seeds of guilt and fear. . . . Adequate--but slow, unoriginal, and certainly not ""Jubilee"" material.